Photovoltaic inverters with selective shutdown in the event of an arc flash and a photovoltaic arrangement with such a photovoltaic inverter

Abstract

A photovoltaic inverter (1) comprising a feed-in inverter (6) configured to extract electrical energy stored in a DC link (7), to convert the extracted stored electrical energy into an AC link, and to feed the converted electrical energy into a supply network (2), a plurality of photovoltaic inputs (8) for at least one photovoltaic module (3) or at least one photovoltaic string (4), an arc detector (12) configured to detect the occurrence of an arc event at one of the photovoltaic inputs (8), and a plurality of DC / DC converter groups (10) connected between a respective subset of the plurality of photovoltaic inputs (8) and the DC link (7) and configured to adjust the voltage at the respective subset (8,16) to extract the respective PV electrical energy available at the photovoltaic inputs (8) and feed it into the DC link (7), and a control unit (13) connected to at least the arc detector (12) and the feed-in converter (6), wherein the arc detector (12) is also configured to indicate to the control unit (13) with a signal the subset (8, 16) of the photovoltaic inputs (8) at which the arcing event occurred, and wherein the control unit (13) is configured to interrupt the supply of PV electrical energy to the DC link (7) at only the indicated subset (8, 16) of the photovoltaic inputs (8) upon receiving the signal from the arc detector (12), characterized in that the feed-in converter (6) is also configured to regulate a DC link voltage of the DC link (7) to a first operating voltage,wherein the control unit (13) is also configured to control the feed-in converter (6) in response to the signal from the arc detector (12), to regulate the intermediate circuit voltage to a second operating voltage which is higher than the first operating voltage.

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